<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      let isPalindrome = function (x) {
        console.log(x)
        for (let i = 0; i < x.length; i++) {
          if (x[i] !== x[x.length - i - 1]) {
            return false
          } else {
            return true
          }
        }
      }
      const num = prompt('请输入一个数字')
      console.log(isPalindrome(num))
    </script>
  </body>
</html>
